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Glow in the Dark Cats
Bioluminescence Yes, there are cats that do, in fact, glow in the dark. How, you ask? The answer is bioluminescence. Bioluminescence is otherwise known as an organism’s ability to produce and emit light. This ability is specific to organisms such as jellyfish, fungi, and insects, but not cats (1). These organisms are able to produce flashes of blue light through a quick release of calcium which then interacts with a protein called aequorin. This blue light then becomes green via green fluorescent protein (GFP) (2). In 1961, Nobel Prize winner Osamu Shimomura and colleagues were able to isolate these proteins responsible for bioluminescence in a jellyfish species known as Aequorea victoria. They soon learned that any organism could be genetically modified to become bioluminescent and emit light through the incorporation of the DNA sequence of these proteins into the genome (1). GFP and AIDS in Felines Both aequorin and GFP are important tools in biological research. Typically used to monitor the activity of individual genes or cells in organisms, green fluorescent protein has an especially large presence in the world of research. Bioluminescence tags were originally used in single-celled proteins, however with technological advances, scientists are able to insert the protein into multi-celled organisms such as cats. Through the insertion of GFP, scientists are able to harmlessly and easily determine if the cat's genes have incorporated the protein. By doing so, they have determined that those successfully tagged with green fluorescent protein would be able to incorporate other protective traits into their genome. In the name of AIDS research, scientists inserted a retrovirus-blocking protein into these cats. Because they were also glowing, they displayed notable resistance to Feline Immunodeficiency Virus (FIV), the virus causing feline AIDS. The gene used in protection against FIV is a restriction enzyme called TRIMCyp and was originally isolated from a rhesus monkey. By using a technique known as gamete-targeted lentiviral transgenesis, scientists were able to insert these genes into a cat’s eggs before sperm fertilization. As a result, the kittens were born FIV-resistant and bioluminescent (not to mention healthy). Although this method is by no means a direct treatment for AIDS, scientists are using it to further understand the role of restriction factors in gene therapy. Since Feline Immunodeficiency Virus is very similar to Human Immunodeficiency Virus, researchers hope this may shed light on treatments for both forms of the disease (3). References 1. Shimomura, O., Johnson, F., Saiga, Y. (June 1962). "Extraction, Purification, and Properties of Aequorin, a Bioluminescent Protein from the Luminois Hydromedusan, Aequorea". Journal of Cellular and Comparative Physiology ''59 (3): pp. 223-239. DOI: 10.1002/jcp.1030590302. Retrieved from http://onlinelibrary.wiley.com/doi/10.1002/jcp.1030590302/pdf 2. Shimomura O (August 1995). "A short story of aequorin". ''The Biological bulletin 189 (1): 1–5. doi:10.2307/1542194. JSTOR 1542194. PMID 7654844. 3. Nellis, R. (2011, September 11). "Mayo Clinic Teams with Glowing Cats Against AIDS, Other Diseases: New technique gives cats protection genes." Retrieved from http://www.mayoclinic.org/news2011-rst/6434.html 4. Shimomura, O. (January 2005). "The discovery of aequorin and green fluorescent protein". Journal of Microscopy 217 (1): pp. 3-15. Retrieved from http://www.cooperlab.wustl.edu/PracticalAdvice/Shimomura2005.pdf